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Geared Drives LS1 for RV-10

gipsowh

Active Member
Last night we posted a new video (5 min.) on YouTube to show a new Chevy LS1 installation by Geared Drives on my RV-10. The video was taken recently during a test to set the prop governor. The engine runs beautifully and I'm looking forward to flying behind it in a few weeks time. We hope to be able to bring the 10 to Sun N Fun in April which means alot of flying once I get the FAA inspection done and completing the required 40 hrs for Phase 1 testing. I'm also looking forward to making Oshkosh and meeting other RV'ers from around the country.

Bill Gipson
N730WL
40227
Conroe, Texas

"Not quite an airplane yet"
 
Weight & Balance

Bill...I'll be following this with great interest. I'd love to know your overall weight so far if you have it...along with an idea of how the aircraft is equipped in order to get some sort of reasonable assessment of the Geared Drive package weight as compared with an IO-540 or Vesta. Thanks

Dan V
Chicago
RV-9A Tailkit
 
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<<We hope to be able to bring the 10 to Sun N Fun in April which means a lot of flying once I get the FAA inspection done and completing the required 40 hrs for Phase 1 testing.>>

Bill, can I recommend a mental re-set? Test flying a new conversion with a Big Show deadline isn't the best plan. Trust me please; been in your shoes and have the t-shirt. If it works great, fine. If it hiccups, take your time, there's always next year. In fact, the whole point is to make sure there is a next year.

You have a nice package. It's the little things that will get you.
 
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I have the sincerest hope that this V-8 conversion is the one that succeeds. Its the cleanest, best laid out conversion I have seen. Bud is a nice guy and really knows his stuff.
 
Congratulations! It took us a year and a half from where you are now to flying! Shoot for Osh! Sun-n-Fun is way to close! It might even be to close for me to make it! You will enjoy flying it though!
What gear ratio are you running?
You are very lucky to have a very knowledgeable engine builder and flyer there. Remember it is a car engine in an airplane and throw out any airplane engine knowledge.
Is Bud going to do the test flight?
 
So smooth....so much power!

I hangar right next to Bud's operation, so I get to see this on a daily basis. You just can't believe how smooth & powerful this operation is. At 3k rpm it just seems like more power than you would ever need. The PSRU speaks for itself, but what I really think is a huge part of the application, is the way the cooling system is done. It is absolutely a work of art, very effective, while keeping the weight towards the CG. I think weight is comparable to a 540.

Bud's new smaller drive for Sube's is test bedding right now, you can put your hand on the drive after running for an hour and its is barely warm. Hope this all works for Bud, he truly is one heck of nice guy.
 
Congrats Bill. Sounds great. I'll second Dan's thoughts here. It's all new and unproven however so finish Phase One and then some before making big plans.

Best of luck and we are all interested in your Weight and Balance!:):cool:
 
You just can't believe how smooth & powerful this operation is. At 3k rpm it just seems like more power than you would ever need.

The PSRU speaks for itself, but what I really think is a huge part of the application, is the way the cooling system is done.
I believe the operation is smooth and extremely powerful.

Has the cooling been tested aggressively with the cowl on? Mine barely warms up with the cowl off but will heat up with the cowl on.
 
FAA Inspector is on deck...

Thanks to everyone for their concerns and positive comments. The deal is we will take the 10 to Florida only when we are ready. We are in no hurry and will not cut corners for the sake of making the show. We had hoped to make Sun N Fun, but if we don't, there is always Oshkosh. So far the package has been relatively trouble free and any hicups have been quickly resolved by Bud Warren and Larry Perryman.

As far as weight and balance... we did a preliminary weighing with scales and the total weight came out to be 1660 lbs. This includes 20 lbs in the tail after checking cg calculations. As it was preliminary, the windshield, fairings, cowling, wheel pants, interior and paint were not installed. Of course we will reweigh and recalc the cg prior to FAA inspection. Bottom line is that the Geared Drives package for my RV-10 will be comparable to other 10's equipped with the IO-540 engine. I was concerned about cg and weight, but after seeing the preliminary numbers, that went away. I will be sure to post final W&B once we get there as there seems to be much interest. As far as my plane goes, it is equipped for day/night VFR and was built pretty much according to Van's plans.

I opted for the 1.5625 ratio gear box. Plenty, plenty power. I'm anxious to see just how economical the LS1 will be with the constant speed prop. Once we fly, I will post the performance numbers as well. Bud keeps telling me that this engine/prop will make my airplane climb like a rocket!;)

I am grateful to have Bud and Larry in the same hangar. Believe me, I would be at least one light year behind where we are now if it weren't for these guys. They really know their stuff.

Bill Gipson
Conroe, Texas
 
Has the cooling been tested aggressively with the cowl on? Mine barely warms up with the cowl off but will heat up with the cowl on.

Todd, we ran the demo LS1 with a Hartzell. cowled up in an RV10 demo cowl last year before & after Sun&Fun extensively, cowling it up really wasn't a factor, it continued to cool well within operating limits. Of course it was just sitting there (staked down) at about 2500 rpm static, I would hope it would even cool better in the air. Just my observation.
 
Cooling in the air is not a problem at all. The only time I could get the temp really high was running take-off power on the ground for 15-20 minutes. It will be enjoyable to have several chevy powered RV-10's out there.

The planes weight is great.

I think with you running that gear box should put you at about 260hp with the prop at 2700rpm.
 
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Great News!

Last week we had the DAR inspection and now I'm the proud owner of an airworthy RV aircraft after 5 years of plotting, some waiting, and building. The inspection went very well with only a few very minor things the DAR had to point out. I had asked an EAA tech counselor to take a look at my RV-10 a week prior and he really gave N730WL a good going over. Its the forest and the trees thing guys. I highly recommend doing such before your final inspection. The more sets of eyes, the better. I had gone over and over and over and just plain missed stuff that I should have taken care of. :eek:

After we "installed" all the interior fabrics, fairings, etc. the total empty weight came out to 1727 lbs., a little heavier than I had hoped, but there it is. I could opt for a different prop as I have a big metal 3-blade Hartzell CS. This weight also includes 25 lbs in the tail for cg purposes at empty. Not too concerned with it being me and my wife (and her shoes) for 95% of our flying and plenty of HP up front.

We are currently buttoning up the fairings and inspection hatches and making plans for first flight. Making Sun N Fun does not look likely, but we will certainly have performance and fuel burn numbers by then.

I must give my building partner Larry Perryman and Bud Warren with Geared Drives much credit for their help in turning a pile of aluminum, fiberglass, wire, and steel parts into a real flying machine. These guys are good!

Bill Gipson
N730WL
LS1 powered RV-10
 
After we "installed" all the interior fabrics, fairings, etc. the total empty weight came out to 1727 lbs., a little heavier than I had hoped, but there it is. I could opt for a different prop as I have a big metal 3-blade Hartzell CS. This weight also includes 25 lbs in the tail for cg purposes at empty.
Bill Gipson
N730WL
LS1 powered RV-10

Do you look at the three blade composite Hartzell that I am running on my RV-10? It is quite a bit lighter than the metal one.

Rob Hickman
N402RH RV-10
 
The order form is now on Van's site.. 15k+... something like that for the 3 blade.... just under 11k for the two blade... :)
 
Dual Batteries

Yes, the weight includes the dual PC 680 Odyessey batteries w/solenoids installed just behind the rear bulkhead. (Leftovers from the Subie install.:)

We need to get more time on the engine, taxi test, etc. I'm hoping to be able to fly before March 15. Like I said in an earlier post, really no major issues slowing us down, just don't want to rush it.

Bill Gipson
Conroe, Texas
 
Do you have the first brave soul picked out yet? I was more than happy to let my building partner do the first flight.

The problem with some of the ground testing is that the plane has so much power at full throttle that it will just drag the tires across the ground with the brakes on.
 
First Flight Coming Up

20090219184700


We haven't finalized plans for first flight, but it is dead ahead. No decision on who's going to do it. There are several items that need attention. Currently performing ground taxi tests and monkeying with the instrumentation. Yesterday, outside temps got up to 80 degrees. Highly unusual for February in Houston. Global warming? Nah. Anyway, water temps were higher than expected after a long taxi. RV-10 drivers know that taxiing a 10 takes some getting use to. I plead guilty to overuse of the brakes and this doesn't help keeping up the taxi speed. So we are working to improve the airflow across the radiator. Bud Warren says he has several tricks up his sleeve to improve the situation. Its good to know someone who has been down this road before.

Hope the photo shows up.

Bill Gipson
Rv-10
LS-1 Power by Geareddrives
 
Prop Diameter

Ross, the prop is a 78" diameter Hartzell prop which is 2" shorter than Van's prototype.

Bill
 
Thanks for the update Bill. Keep that engine cool. It ain't pretty when she heats up.
 
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suprisingly conventional?!

Bill, Nice looking aircraft. I might also mention that you managed to keep every thing with a very "finished" look which is often difficult. I'm sure Buds help was a great asset there. I'm looking forward to your flight results, as is just about everyone I guess.
Bill Jepson
 
9 days and no info? Your kill'n me! Am I the only one chomping at the bit to see some numbers on this setup? C'mon, I'm waiting on those 200mph @ 8gph that I've been reading all about:rolleyes:
J/K, hope everything is going well and as planned.
y-it
 
No Real Information Just Yet...Working on it.

OK, OK. Sorry, I've been holding out until I get more information to report. All is well.. sort of. Here is what I know at this ten seconds.

Last Wednesday, Bud Warren flew N730WL for the first time. She flew beautifully. I think Bud was impressed with how easy the RV-10 is to fly. He has many hundreds of hours in fixed wing and was the logical choice to make the first flight. The Geareddrives LS-1 package was flawless. Temps never over 157 degrees F. OAT was 80+F. N730WL has been around "the patch" on several flights now with us trying to get a "used" prop governor to work. (My idea to get a bargain off of Barnstormers:mad:). It's fine on runup on the ground, but won't work in the air. Friday we installed a different prop governor and finally got something to work in the air.

Another run around the airport late Friday and Bud got the prop to kick in. He reported 145 knots with 3200 engine/2050 prop RPM's pulling 22 inches of Hg manifold pressure. Obviously, there is plenty of HP/prop left. Nothing with this particular governor has been optimized, (we just installed it late in the day and tried it) but it's an indication of how fast this plane will be able to go. I mean 165 mph with out even trying!!

We got what I hope was the last cold front of the year thru Conroe on Friday night dropping the temperature into the lower 30"s and blowing 25-35 mph on Saturday and Sunday. No flying...

We will be flying tomorrow morning and hope to get some better numbers to share.:D

It's exciting times around here.

Bill Gipson
Conroe, Texas
LS-1 powered RV-10
 
Big congrats Bill! Nice to have that kind of relationship with your engine vendor.

Looks like you're gonna have to watch Vne on this bird too. You've hardly tapped the hp in that beast yet, I'm thinking that is only about 40% power!

Can't wait for more numbers.:):cool:
 
Update - Not really

Not much information to pass along. We've been on vacation for Spring training in Florida. Think we've got the governor problem solved, so N730WL is ready to fly. Now the weather in Houston has turned to ****, so it might be a couple of days before we can go out and play. My test pilot (Bud Warren) is on the mend from surgery, so our progress has slowed. Really would like to get the hours flown off before Sun N Fun. It's going to be close.

Promise to post numbers when they are first available.
 
So........
Been gone for a while mov'in and such but I'm really interested in your stats. I spoke with Bud a couple days ago and he spoke of some pretty amazing fuel/speed numbers but I want to verify.
y@




Not much information to pass along. We've been on vacation for Spring training in Florida. Think we've got the governor problem solved, so N730WL is ready to fly. Now the weather in Houston has turned to ****, so it might be a couple of days before we can go out and play. My test pilot (Bud Warren) is on the mend from surgery, so our progress has slowed. Really would like to get the hours flown off before Sun N Fun. It's going to be close.

Promise to post numbers when they are first available.
 
We ran into Bill and his wife with their Chevy-powered -10 at Brenham last weekend and had an enjoyable lunch talking about the plane. I found the the most intersting thing to be the clutch - you can stand there and freely move the prop when it is sitting on the ramp - sort of like a free-spool turboprop - very cool!

Paul
 
Free spinning

We ran into Bill and his wife with their Chevy-powered -10 at Brenham last weekend and had an enjoyable lunch talking about the plane. I found the the most intersting thing to be the clutch - you can stand there and freely move the prop when it is sitting on the ramp - sort of like a free-spool turboprop - very cool!
Paul

That was something I was thinking about with that conversion. It would be a good idea to carry a "prop stop" bungie to prevent spinning in a high wind gust at an airshow! The prop could spin and the momentum might actually ding somebody.
Bill Jepson
 
Our Air Tractors come with a prop bungie

...since there's no compression and the prop spins freely in the wind. One of the main reasons we tie the prop is because there isn't any oil pressure with the engine off and the dual planetary gearsets turn 17 times the prop RPM's if it spins. I'd think the Geared-Drive gearboxes may not have their own internal oil pump either, running in an oil bath instead.

Regards,
 
oil pumps

according to the geared drives web site.....their unit has its own oil pump. They didn't want to rely on just an oil bath which is smart.
 
Me thinks that bath lube for a gearbox works just fine, hundreds of millions of manual gearboxes and diffs on cars work just fine for decades with this setup. My PSRU has never been off the engine, backlash is unchanged in over 300 hours, bath lube.

Separate pumps make sense to drive a hydraulic prop or if the box has highly loaded journal bearings. Otherwise it's just one more thing that can fail.
 
Oil Pump - Geared Drives

I tried to respond this morning from my new I-phone... no go. Operator error for sure.

The geared drives PSRU has its own reservoir and oil pump to supply pressurized gear oil to the gear bearings while also providing pressurized oil to the prop governor. Very reliable pump with no failures to date. Bud had a bearing problem way back when and traced it to inadequate splash lubrication, thus the direct pressurized lubrication. Problem solved.

I've been very happy with the FWF package so far. Just now have the 40 hrs flown off without any major issues except the prop governor debacle. This was my doing and nothing to do with the gearbox:eek:. The RV-10 flies terrific and the engine is smooth. I'm still getting use to handling the horsepower especially on take-off. Just can't shove the throttle to the firewall but rather have to feed it in up to max 4300 RPM as the rudder authority kicks in. The only nagging issue to date is the O2 sensors apparently not communicating with the aftermarket computer. While the engine seems to run just fine without "seeing" the O2 sensors, I just don't know at this point if this is "normal". We are seeking the help of a GM expert and are working it.

Last weekend my wife and I made our first cross country to Brehnam (50whole nm). Shared table with Paul, Louise and two other Conroe pilots. Interesting conversations!! The plane performed well and the TO and landings were good. Now she wants to know where we will be going next!:)

Hope its cooler where you are....
 
Got that 40 hours on there quick, good job!

Bill, got any TAS/ fuel flow numbers yet. We are all dying to know how the LS compares to an IO.

You burning 100LL or mogas?
 
Bill,
I think we are all curious including myself what your fuel burn rates are. There is a simple way to monitor the O2 sensors. Autozone or Advance auto sell an O2 meter for less than $100. We mounted ours in the panel and you can monitor it yourself.
 
speed/fuel burn

OK...... even us lurkers are going nuts! 40 hours, there must be some fuel burn at certain speed numbers. Please.... even if they are preliminary.
Daryl
 
Geared Drives Powered RV-10 Fuel Burns

Here are some RAW numbers that I have to date. These are going to change some since Bud upgraded my gearbox with a slightly different ratio. Was 1.562 and is now 1.616. Haven't flown any test patterns with the new gear box yet. Planning to go up to altitude late this afternoon and make some runs. It's not fun just now with 98F heat in Houston.

Burning 100 LL 100% of the time. RPMs are Engine/Prop Prop is 3-bladed 78" Hartzell Scimitar CS The following numbers were recorded while flying at 6000' on a relatively calm day. Just me so the plane was lightly loaded.

At 24 in. MAP: 3500/2240 RPM 185kts and 11.7 gph, 3200/2050 RPM 175kts and 9.6 gph

At 22 in. MAP: 3300/2110 RPM 166kts and 9.1 gph,

At 20 in MAP: 3700/2370 RPM 170kts and 9.4 gph, 3500/2240 RPM 168kts and 8.6 gph
3300/2110 RPM 167kts and 8.0 gph

At 18 in MAP: 3700/2370 RPM 159kts and 7.9 gph

How do these numbers compare to an IO?? Ya'll tell me.

We are looking forward to flying this bird cross-country at an economical cruise setting around 165 kts. Just because I've got the horses doesn't mean I need to try to break the sound barrier. Not that kind of flier.

We are planning to take a couple of CC trips prior to Oshkosh so that my wife can get use to the plane prior to the BIG trip. Also when we get new numbers, I'll post.
 
Bill those are great numbers. My ratio is 1.72. I don't have any straight and level numbers yet. Now that the plane is ready I don't have the time.
 
First,
I know zero about this engine/prop/gear combination.

I would say it is very unlikely you are making 185kts at 11.7 gph in an RV-10.

Looking at all your numbers, none look even close to reality.
 
First,
I know zero about this engine/prop/gear combination.

I would say it is very unlikely you are making 185kts at 11.7 gph in an RV-10.

Looking at all your numbers, none look even close to reality.

I think your first statement is probably correct.
 
Thanks for the preliminary data points Bill.

I know the Lycoming guys don't want to believe at this point, they are still smarting from Randy's STI/ 7A numbers. You qualified this as raw data. We await further data from longer cross country trips when you have it. I know others also appreciate any of your posts here.

I know the Robinson LS-1 Seabee conversions ended up burning 20% less fuel at the same TAS as the original Franklin. I think they have close to 1200 hours now on the first aircraft and several more are flying now with other LS engines.

It really would be nice to have a good alternative to the IO-540 for the -10s.
 
First,
I know zero about this engine/prop/gear combination.

I would say it is very unlikely you are making 185kts at 11.7 gph in an RV-10.

Looking at all your numbers, none look even close to reality.
As a comparison, what TAS vs fuel flows have you seen flying Lycoming powered RV-10s?
 
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